It is known that gallstones occur in the biliary tract and that the majority of these gallstones are composed of cholesterol. Access to the biliary tract may be obtained endoscopically, or after surgery by a T-tube.
In the past, organic solvents, such as ether or chloroform, have been used; but these are poorly tolerated by patients. Controlled studies reporting efficacy have not appeared in the medical literature. Five years ago, Dr. Alan F. Hofmann, then at the Mayo Clinic, in collaboration with Dr. Gordon Flynn and Dr. William I. Higuchi of the College of Pharmacy of the University of Michigan, found that mono-octanoin was an excellent solvent for cholesterol. Subsequently, they learned that this material was available as a commercial emulsifier (Capmul), manufactured by Capitol City Products, a subsidiary of Stokely Van Camp, Inc. In subsequent work, these investigators showed that this compound could be infused into T-tubes and would cause gallstone dissolution in some patients.
U.S. Pat. No. 4,205,086, issued May 27, 1980, covers the use of fatty acids and/or alcohol esters thereof, specifically, glyceryl-1-monooctanoate (monooctanoin, which is referred to above by the tradename Capmul). The physical properties and clinical application to monooctanoin is disclosed in Gastroenterology 78:1016-1022, 1980.